Phase diagram of the Bose Kondo-Hubbard model

We study a bosonic version of the Kondo lattice model with an on-site repulsion in the conduction band, implemented with alkali atoms in two bands of an optical lattice. Using both weak and strong-coupling perturbation theory, we find that at unit filling of the conduction bosons the superfluid to Mott insulator transition should be accompanied by a magnetic transition from a ferromagnet (in the superfluid) to a paramagnet (in the Mott insulator). Furthermore, an analytic treatment of Gutzwiller mean-field theory reveals that quantum spin fluctuations induced by the Kondo exchange cause the otherwise continuous superfluid to Mott-insulator phase transition to be first order. We show that lattice separability imposes a serious constraint on proposals to exploit excited bands for quantum simulations, and discuss a way to overcome this constraint in the context of our model by using an experimentally realized non-separable lattice. A method to probe the first-order nature of the transition based on collapses and revivals of the matter-wave field is also discussed.Comment: 10 pages, 5 figures, V2: extended discussion of effective Hamiltonians and mean-field theory, added Fig.

Social-ecological resilience in organic and non-organic cocoa farming systems in the Yungas of Bolivia

Cocoa based small scale agriculture is the basic livelihood of most farming families in the region of Alto Beni in the Bolivian Andes. Cocoa cultivation is affected by climate change impacts, soil degradation, pests and plant diseases, and insecure cocoa prices. From a sustainable development point of view, cocoa farms need thus to become more resilient. Resilience refers to the ability within a farming system to reduce the sensitivity to stress factors while maintaining productivity, the capacity for self-organisation, to learn, and to adapt to change. Resilience can be subdivided in the three features buffer capacity, self-organisation, and adaptive capacity. This study addresses differences in resilience of organic and non-organic cocoa farms, and the most important features that influence social-ecological resilience in cocoa farming systems. Indicators for resilience were defined in a transdisciplinary process with local experts and cocoa farmers in a workshop and focus groups. Indicators for buffer capacity were tree diversity, crop diversity, and the diversity of income sources of the farming family. Indicators for self-organisation were the interaction with farmers’ organisations, their subsistence level, cocoa yields, and the annual family income. Adaptive capacity was assessed by inquiring the number of courses on cocoa cultivation family members had participated in, and the number of information sources they had. We interviewed 52 certified and non-certified households and conducted an in-depth participant observation with 15 households from the sample. It resulted that organic farms in the research area were more diversified (tree species in cocoa plots: 4.4 vs. 1.9, crop diversity: 8.4 vs. 6.7 crop varieties on cocoa farms), and had higher cocoa yields (506 kg ha−1 yr−1 vs. 335.8 kg ha−1 yr−1, both without external inputs). Annual family income was significantly higher on organic farms with 7530.2 vs. 6044.4 USD. Organic farmers had participated in more courses on cocoa cultivation which may be the main reason for the better performance of their farms. We conclude that resilience building was enhanced by local organisations that organise organic certification and go further than basic organic certification principles by providing extension services, tree seedlings, capacity building, and certain social insurances

Geographic and Demographic Bank Outreach: Evidence from Germany’s Three-Pillar Banking System

This paper investigates the performance of Germany’s three-pillar banking system in providing financial services nationwide, regarding different outreach indicators. At the federal state level, bank outreach shows South-North and West-East gaps. Combining regional and bank data at the district level for 2005, we examine the determinants of geographic and demographic branch penetration of the regional savings and cooperative banks. Both banking groups provide a larger branch penetration in more wealthy regions, but maintain a larger number of branches per inhabitant in less densely populated regions, easing access to retail banking services. With their comparatively large branch penetration in less wealthy regions, public savings banks help to reduce regional economic disparities. The branch penetration of both banking groups increases with the share of elder people and bank size in a region. Because of their public mission to serve all regions, public savings banks foster competition. Geographische und demographische Reichweite von Banken: Empirische Evidenz für Deutschlands Dreisäulen-Bankensystem. Der Beitrag untersucht die flächendeckende Bereitstellung von Finanzdienstleistungen durch das deutschen Dreisäulen-Bankensystem, wobei unterschiedliche Indikatoren der Reichweite betrachtet werden. Auf der Ebene der Bundesländer zeigen sich Süd-Nord und West-Ost-Gefälle. Durch Verknüpfung von Regional- und Bankdaten auf Kreisebene für das Jahr 2005 werden die Determinanten der geographischen und demographischen Bank- stellenpenetration der regional tätigen Sparkassen und Genossenschaftsbanken untersucht. Beide Bankengruppen zeigen eine höhere Bankstellenversorgung in wirtschaftsstärkeren Regionen, unterhalten aber mehr Bankstellen pro Einwohner in dünner besiedelten Regio- nen, womit sie den Zugang zu Finanzdienstleistungen erleichtern. Mit ihrer relativ großen Bankstellenpenetration in wirtschaftsschwächeren Regionen tragen die Sparkassen zur Überwindung regionaler ökonomischer Disparitäten bei. Die Bankstellenversorgung bei- der Regionalbankgruppen steigt mit dem Anteil älterer Menschen und der Bankgröße in einer Region. Durch ihren öffentlichen Auftrag, alle Regionen zu versorgen, tragen die Sparkassen zur Sicherung des Wettbewerbs bei.Banks; Market Structure, Firm Strategy, and Market Performance; Firm Objectives, Organization, and Behavior

Economic Recovery in the Euro Area and in Austria in a Dynamic Global Economic Environment

Economic Recovery in the Euro Area and in Austria in a Dynamic Global Economic EnvironmentEconomic Growth

Abordagens de ensino e aprendizagem de línguas : comunicativa e intercultural

This article discusses the communicative and the intercultural approaches to language teaching and learning. Firstly, it describes the core theoretical principles, goals, and the roles of teachers and learners in both approaches, as well as the way they are treated in different German textbooks. Secondly, it discusses a set of core principles and concepts (‘activity’, ‘interaction’, ‘motivation’ and ‘communicative posture’), as well as the didactic-pedagogical implications of implementing a communicative approach to language teaching and learning. Finally, it includes a reflection about the necessity for the language teacher to develop an intercultural background, as well as the eclectic use of different linguistic theories and language teaching approaches to make the acquisition of communicative and intercultural competence viable

As (des)sonorizações e a neutralização da vibrante : atitudes e concepções lingüísticas

This article discusses linguistic attitudes and conceptions (beliefs and prejudices) of 20 teachers regarding the ‘German accent’ ((de)voicing of consonants and neutralization of the vibrant) and their implications in their social practices in school lessons, in three German-Portuguese bilingual communities in Rio Grande do Sul. To conclude with, a reflection about how teachers’ conceptions relate to the treatment they dispense to linguistic traces in face to face interactions. The present investigation is inserted in the Interactional Sociolinguistics and in the Sociolinguistics field, specifically in linguistic variation and bilingual studies, and it is especially rooted in linguistic attitudes and conceptions. This research matches instruments and analytical categories of both quantitative and qualitative approaches, examining both teachers’ practices and their linguistic attitudes and conceptions. The results point to educational and identity conflicts which are reflected in speakers’ attitudes of solidarity or linguistic differentiation regarding the use and rating of linguistic variation, as well as in the treatment dispensed to the linguistic features of these communities

Ayasofya

Taha Toros Arşivi, Dosya No: 102-Camilerİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Bancassurance in the Italian life insurance industry. An analysis of scale economies, concentration and risk profile

This dissertation is composed by three separated articles and carries out an analysis of the effects of bancassurance ties in the Italian life insurance industry from several perspectives. Departing from an analysis of the relevant literature, two separated empirical econometric analyses are developed focusing on the effects of bancassurance respectively on scale economies and on insurers\u2019 asset risk profile. We consider the Italian market due to the importance of bancassurance ventures, its diversified life insurance sector, its recent volatility and its compliance with European and country-specific regulation. Our analyses focus on responses to regulatory and macroeconomic changes looking at competition (of which scale economies can be considered an indicator), concentration and investments\u2019 choices (asset risk profile). The general literature on bancassurance has analyzed the optimal way to enter the insurance market mainly from the bank point of view. Less attention has been paid to insurers\u2019 standpoint. In the first part of the dissertation we critically discuss the main issues on bancassurance studied so far and we highlight existing gaps. In particular we suggest to study the cooperative agreements between banks and insurers by using. In our view this approach, which has already been applied to the analysis of the co- existence of several distribution channels, is also appropriate to explain the co \u2013 existence of different degree of integration between banks and insurance companies. The second part of the dissertation investigates the existence of scale economies into the life insurance industry in Italy, looking for differences in the level of optimal scale across bancassurance groups. The originality of this study lies in fastening together two separated strand of literature: the general literature on financial conglomeration, in particular on bancassurance ventures, and the studies concerning the existence of scale economies in the life insurance market. In general, relying on the financial conglomeration literature, we expect that bancassurance groups are better able to exploit scale economies. We considered the span 1998 \u2013 2012 dividing the panel into three groups based on ownership linkages with banks. Relying on a micro - econometric procedure, two cost functions are estimated dividing the span into pre crisis and post crisis periods. Results show that, before the crisis hit, insurers independent from banks operated on their optimal scale while bancassurers operated at decreasing return to scale, thus no further conglomeration was needed within the sector, in particular with respect to bancassurance groups. After the crisis results indicate overall increasing return to scale although the industry has undergone substantial consolidation. Taking into consideration the enhancement of managerial and supervisory actions on risk-taking activities of financial firms after the crisis, in the third part we analyse changes in Italian life insurers\u2019 asset risk profile in the span 2005 \u2013 2011, accounting for the importance of effects of bancassurance ventures. Through a pooled OLS panel data analysis we test the finite risk hypothesis which predicts a negative correlation between asset risk and other firm-specific factors determining the level of risk exposure such as bancassurance ventures, product mix, size and product diversification. In particular we contribute to the extant literature by considering the effects of the adoption of specific bancassurance models on the level of asset risk. The hypothesis is developed relying on two strands of literature: the general literature that investigates the relationship between asset risk and capital and on the specific studies dealing with risk exposure determined by bancassurance ventures. Finally we test for the effects of external macroeconomic shocks (such as the last financial crisis and changes in regulation). Our results show that Italian life insurers present a relatively prudent level of exposure, which is negatively correlated with firm factors influencing the overall risk profile. Stronger bancassurance models confirm this relationship. Finally, asset risk exposure did not decrease significantly as a result of the financial crisis, pointing at the effectiveness of regulatory restrictions on investments or a contingent search for yields

Recreating the image of women in Mexico: a genealogy of resistance in Mexican narrative set during the Revolution

Traditionally, women have been relegated to the margins of society, history, and culture in male-dominated environments. Patriarchal systems have long denied women to play an appropriate role in nation building and to enter the public sphere, as is the case in Mexico. The female participation during one of the country’s most critical periods, the Mexican Revolution, has largely been ignored. Through situating their narratives into the context of the Revolution and describing the obstacles and limiting conditions that women experience, Mexican writers such as Elena Poniatowska and Laura Esquivel criticize the status quo of social and gender politics in Mexico and attempt to re-inscribe the female experience into the nation’s history. In this thesis, I use Alison Stone’s approach of feminist genealogy to examine women’s resistance in Hasta no verte Jesús mío by Elena Poniatowska and Como agua para chocolate by Laura Esquivel. For this purpose, I examine the specific representations of feminine identity and analyze the similarities and differences between the women writers’ and protagonists’ modes of resistance both on intra- and extra-textual levels while taking into account the different contexts and settings in which female resistance against patriarchal oppression occurs. The investigation reveals the various overlaps of the resistance strategies that the women apply regardless of time and place. Furthermore, understanding their resistance in a genealogical context allows them to establish connections with each other in order to provide mutual support in a patriarchal environment. The analysis also shows that the feminist genealogical approach is useful for women in Mexico and Latin America in general as it helps them to perceive themselves as a coalitional group despite any social, cultural, and political differences and is therefore a constructive way of putting forth the women’s movement in the region